We would like to thank the following people for their help in completing this article:-1st Lt Joshua Pena (WTI Public Affairs)Sgt Cody Haas (1 MLG Public Affairs)

Maj T. Drieslein and the crew of 'Draft 81'

It's not only flight crews that attend WTIMaintenance still has to be carried out between flight ops' and it is essential that groundies get to attend the course as well

Each WTI is held over a period of seven weeks; three of which are academic and four of which involve the flight phase. The number of live aircraft sorties and the sheer size of the WTI continues to serve as the best training venue to support developmental and operational testing for the USMC. Common Aviation Command and Control System Phase II (CAC2S) made its debut at WTI 1-15, where the Tactical Air Command Centre, Direct Air Support Centre and Tactical Air Operations Centre operated out of three different operations facilities.

To protect the sensitive electronic warfare suite on the Prowler, they operated from some of the plentiful sun sheds available at Yuma

This Iwakuni based Hercules aerial refueller awaits another mission at MCAS Yuma

Ready for action, this UH-1Y Venom awaits the crew for its next mission

A Reserve FA-18C Hornet from VMFA-112 based at JRB Fort-Worth takes on fuel from a KC-130J Hercules

As with the other aircraft at WTI, there were AV-8B Harriers from both east and west coast unitsThe aircraft above is a Yuma resident with VMA-214 'Black Sheep'

Most of the UH-1Ys at Yuma were armed with the M134 7.62mm Mini-gun (left) and GAU-21 .50-calibre machine guns (right),in conjunction with either the LAU-61 (left) or LAU-68 70mm rocket pods (right)

The 'Hornets Nest’

Despite the heat, essential line maintenace is carried out on the APG-73 radar of this FA-18D Hornet

With the rugged hills of east Yuma in the background, 'Sheep 52' taxis back to its parking spot after an afternoon mission on 16th April

‘Tilt-Rotor’ Territory

A VMFA(AW)-224 FA-18D Hornet closes in on the KC-130J Hercules tankerMuch of the scuffing and dirt visible around the cockpit and leading-edge extensions on the FA-18 are caused by standard Marine issue size 10s!The tactical paint scheme has always suffered badly from the hands and feet of groundcrew, the rough semi-absorbent paint collecting much of the grime picked up in the tread of boots from the flightline

Electronic warfare is crucial to the success of any MAGTF and so it was not surprising to see aircraft designed for this specific role at WTI 2-15. The main contingent were the Grumman EA-6B Prowlers of VMAQ-3 'Moondogs', based at MCAS Cherry Point, North Carolina, with a single United States Air Force (USAF) Boeing E-3 Sentry from the 964th Airborne Air Control Squadron and a Boeing E-8 J-Stars from the 116th Air Control Wing supporting them. Operating from some of Yuma's numerous sun-sheds, designed to protect aircraft from the blistering Summer heat that averages 108º F (42º C), but often going as high as 120º F (49º C), the Prowlers worked daily missions during WTI, normally as a single-ship using the call-sign 'Storm'.

This well-used Hornet overflies the typically deserted Arizona landscape during a WTI mission

Marine Corps HMLA squadrons operate a mix of either Bell AH-1W Cobra and Bell UH-1Y Venoms, or a mix of Bell AH-1Z Vipers and UH-1Y's. The Cobras and Vipers are designed to provide close air support (CAS), forward air control (FAC), reconnaissance and armed escort duties, with the Venoms providing airborne command & control, utility support, medical evacuation (MEDEVAC) and additional fire support. The AH-1W continues to provide valuable service to east coast HMLAs, with the AH-1Z having taken over duties with all of the frontline west coast based units and the UH-1Y having completely superceded the old UH-1N version of the 'Huey' back in August of 2014. So important are the HMLAs in supporting the MAGTF, that if and when the Marine 'Grunts' on the ground find themselves under fire and requiring air support, the first thing they ask is; "where are my snakes?"

Combine an average of 313 days of sun per year with some 10,000 square miles available for live firing and it's easy to see why Yuma, Arizona is an ideal location for the United States Marines Corps (USMC) biannual Weapons & Tactics Instructor Course (WTI). Spread over south-eastern California and south-western Arizona, the sheer size of the Yuma Training Range Complex (YTRC) provides the USMC with the opportunity to practice live air-to-air, air-to-ground and electronic warfare training. The latest WTI course commenced March 10th, with the flying element of WTI 2-15 commencing on March 30th and continuing through to April 26th. Jetwash Aviation Photos was invited to spend a few days at Marine Corps Air Station (MCAS) Yuma to report on the aircraft and units taking part in the latest WTI course. With this class scheduled to be the largest ever to graduate from a WTI course, students learned how to apply the latest in air-to-air & air-to-ground combat, air-to-ground communications and humanitarian assistance and disaster relief tactics. Highlights of the WTI included a scenario-based, non-combatant evacuation operation, as well as multiple large-scale, combined arms exercises.

A line of CH-53E Sea Stallions await their next missions at WTI 2-15The majority of missions flown by them occurred late afternoon/early evening

A Beaufort based FA-18C gets airborne late afternoon from Yuma's Runway 03

Although not actively involved in the WTI itself, Yuma's Search & Rescue (SAR) Bell HH-1Ns were always on alert

A small number of aircraft operated by civilian contractors participated in WTIThis ex-Bulgarian Air Force Mil Mi-24D is owned by Vertol Systems, based in Portland, Oregon

'Draft 81' sits on the South Cala at MCAS Yuma

The Bell-Boeing MV-22B Osprey has transformed the US Marine Corps in recent years. Replacing the venerable CH-46E Sea Knight in the medium-lift helicopter squadrons, the Osprey combines the vertical take-off and landing capability of the CH-46, with the speed and range of a traditional fixed-wing aircraft. Put simply, the extended range, higher payload and in-flight refuelling capability has enabled the Marine's medium-lift squadrons to go further, faster and with more men and/or equipment.

FA-18D from Marine All-Weather Fighter Attack Squadron 224 The distinctive Tiger markings on the aircraft rudders leaving no doubt that this aircraft belongs to the 'Bengals'

This nicely marked Bell AH-1W Super Cobra is from HMLAT-303 based at MCAS Camp Pendleton

It was noticeable that all of the Harriers we saw operating during the WTI were of the AV-8B+ version, equipped with the APG-65 radar

Having just returned from a mission and completed a 'hot' refuel

The Plane Captain salutes the Prowler's commander to signal that the aircraft is good to go

‘Snipers’ in DemandVMFT-401 'Snipers' falls under the auspices of 41 (Reserve) Marine Air Group (MAG-41), part of the 4th Marine Air Wing, permanently based at MCAS Yuma. It is the only adversary squadron in the Marine Corps and the only one to fly the Northrop F-5F and F-5N Tiger II. With its primary role being to provide instruction to active and reserve squadrons through dissimilar air combat training (DACT), it is very much in demand during the WTI. In fact it probably flies more sorties than any other unit during the course, with it being a traditionally busy period for the unit.

Having activated on March 18, 1986, as part of MAG-46 (moving to MAG-41 in June 2009) at Yuma, the squadron received a number of ex-Israeli Air Force IAI F-21A Kfirs as their first aircraft, which they flew for some three years before transitioning to the Northrop F-5E Tiger II. The squadron was recognised for flying more than 50,000 mishap-free flight hours, which they achieved in July 2010, having not had a mishap since October 1995. At an average of 45 minutes per flight, 50,000 hours equates to nearly a staggering 70,000 mishap free sorties. Following retirement of the original ageing F-5s, they completed delivery of their current low hour ex-Swiss Air Force F-5E/F mounts in 2008, later upgrading them to F-5N standard with an improved Inertial Navigation System (INS).

Background to the WTI; In 1975, a study group was formed at Marine Headquarters to determine requirements for the enhancement and standardisation of aviation training. Project 19 recommended establishment of the Weapons and Tactics Training Program (WTTP) for the USMC aviation element. The cornerstone of the WTTP was the development of a graduate-level Weapons and Tactics Instructor (WTI) Course and the placement of WTI graduates in training billets in every tactical unit in Marine Corps aviation. Consolidated WTI Courses were subsequently conducted at Marine Corps Air Station (MCAS) Yuma by a combined MAWTU staff in May 1977 and February 1978. Due to the overwhelming success of the WTI Courses, the Commandant of the Marine Corps commissioned Marine Aviation Weapons and Tactics Squadron One (MAWTS-1) at Yuma on June 1, 1978. The MAWTS-1 mission is to provide standardised graduate-level advanced tactical training and to assist in the development and employment of aviation weapons and tactics. Advanced tactical training is accomplished through two WTI courses and two Marine Division Leader Tactics Courses each year.

This decidedly scruffy looking aircraft from VMM-263 was one of a number that made the long journey from the east coast

A Bell UH-1Y Venom from HMLA-467 basks on the Yuma ramp, as it awaits its crew for an evening mission

The busy AV-8 ramp at Yuma, with ground crews loading weapons onto the various hardpoints

One of the most noticeable accoutrements on the AH-1Z and UH-1Ys are the protective covers on the tail rotorThese were added to protect the composite rotor-blades from dust and condensation forming within the blades due to extreme temperatures

MV-22B Ospreys from seven different squadrons attended WTI 2-15

The Lockheed-Martin F-35B Lightning II is the planned long-term replacement for both the FA-18 Hornet and AV-8 Harrier with the US Marine Corps; and it was much in evidence during our time at Yuma whilst reporting on the WTI. Although there were quite heavy restrictions on what we could and couldn't photograph in relation to it, we saw numerous sorties flown by the resident VMFA-121 'Green Knights' each day, both early in the morning, right through until the evening, normally as a flight of two aircraft. The first Short Take-Off/Vertical-Landing (STOVL) Lockheed-Martin F-35B Lightning II (Bureau Number 168717) was delivered to MCAS Yuma on November 16, 2012 with VMFA-121 transitioning from the FA-18 on the same day. The unit had received its full complement of 17 aircraft by December 2013.

Perfectly illustrating how WTI attracts crews and aircraft from all over the globe

VMGR-152 brought two KC-130Js all the way from Iwakuni, Japan

'Loadies' secure an inert GBU-16 Paveway in place on the outer pylon of an AV-8B Harrier II

Paveway IIs being picked up by Marine Corps ordnance crews, identifiable by their red coloured cranials

The HF tail-code on this AH-1W Cobra identifies it as belonging to HMLA-269 'Gunrunners', based at MCAS New River

VMFT-401's fleet of adversary aircraft all benefit from sun shelters that protect them from the hot Arizona sun

As mentioned previously, the South Cala supported the fixed-wing element for WTI 2-15, including five Lockheed KC-130J Hercules tanker/transports from all four active Marine Aerial Refueler Transport Squadrons (VMGR-152, -234, -252 and -352). On 16th April we joined the crew of 'Draft 81' for an aerial refuelling mission on board aircraft #167924. Although a VMGR-352 assigned aircraft from MCAS Miramar, the crew was made up of a mix of personnel from the four units participating in WTI. Along with a further two KC-130Js (call-signs Draft 82 and Draft 83), our scheduled trade for the mission were 'Salem Flight' and 'Latch Flight'; a mix of FA-18s from VMFA-112, VMFA-122 and VMFA(AW)-224.

Just over a dozen CH-53E Super Stallions were in residence at Yuma for WTI 2-15

#161263 is one of the older Stallions in the fleet

Typically clear blue skies above Yuma, as a bowser trundles across the flightline in front of a VMA-214 Harrier II

Some 13,000ft over the Arizona desert, this FA-18 closes in on the refuelling drogue of the KC-130JNote the twin AIM-120 AMRAAMs under the port wing

The United States Marine Corps (USMC) is the United States "force in readiness—ready when the nation is least ready" and as such, the USMC must be ready to deploy under any and every threat condition in every type of climate, anywhere in the world. One of the primary tools the USMC relies upon to bring this capability to life is its aviation element. Marine aviation is an integral and essential part of every Marine Air-Ground Task Force (MAGTF) and the USMC’s aviation element is integrated and forward deployed with every MAGTF. As 1st Lt Jonathan Moss (an AH-1Z pilot) told us; "We are an aviation asset to the guy on the ground"; whilst Capt Patrick Daly (an FA-18 instructor at VMFAT-101, who has first-hand experience of a WTI) added; "You are expected to drop ordnance on target, close to ground troops and within a 15 second timescale". That's exactly why WTI is so important to the Corps and why being selected for WTI is such an honour for those involved.

The CA tail-code indicates that this Cobra is assigned to the 'Sabers' of MAG-29

Being towed to the South Cala is this east-coast based VMA-542 'Flying Tigers' AV-8B+

The Sikorsky CH-53E Super Stallion is a huge helicopter and an essential piece of equipment for the MAGTF

When the US Marine Corps needed to replace its ageing fleet of Douglas A-4 Skyhawks, senior Corps personnel were adamant that they needed a close air support (CAS) aircraft that could literally 'come ashore' with the troops. Many assumed that the Navy's A-7 Corsair II would fit the bill, however despite its heavy weapons load and long range it didn't quite fit the bill. At the time, the US aircraft manufacturing industry was caught on the back-foot and the gap was eventually filled by the licence-built McDonnell-Douglas AV-8A Harrier. Although bearing the same Harrier name as its predecessor, the Harrier II is a completely new design and has supported the MAGTF in the CAS role for some 30 years now. With its ability to take off and land vertically, or operate from short unmade airstrips, it is an immensely valuable asset to the Corps and plans are in place for it to soldier on well into the next decade, until the new Lockheed-Martin F-35 Lightning II eventually replaces it.

One of eleven UH-1Y Venoms at WTI basks in the Arizona sun on the North Cala

Once the initial classroom instruction weeks are completed, the FA-18 Hornet squadrons pilots fly pretty much every other day, down days being consumed with mission planning. The initial flying sequences begin with something such as an airfield strike. This is generally then followed by a close air support (CAS) mission, flown both day and night, working with forward air controllers (FACs) and joint-terminal attack controllers (JTACs). It is then that they begin to integrate with other platforms such as AV-8 Harriers, AH-1 Cobras/Vipers and UH-1 Venoms, all the time having to contend with various simulated threats from the various surface-to-air (SAM) batteries located around the Yuma complex. The next stage involves seeking out and destroying those same SAM batteries, followed up by offensive anti-air and offensive air support missions, again flying both day and night missions; ending with what is known as FINEX (Final Exercise). This culmination will see the FA-18s fly numerous sorties, including CAS, counter-air, escort and strike missions, attacking large complex targets as part of a large force package, which includes all elements of the fixed and rotary-wing aircraft involved with WTI. To re-cap, the whole point of Marine Aviation is to support the guys on the ground; and in essence the MAGTF is key. By creating experts in their field, the WTI allows the students who graduate, to go back to their respective units and train those not fortunate enough to attend a WTI.

HMH-361's 'CAG bird' gets refuelled on the Yuma ramp in readiness for its next flight

Any MAGTF relies on the men on the ground and despite its size the CH-53E is still able to operate from amphibious assault ships. Despite having been in service for nigh on 30 years, there are still some 150 of the type in operation with four east-coast and four west-coast squadrons, together with a single squadron at Kaneohe Bay, Hawaii. With the new CH-53K 'King Stallion' some way off in terms of entering service with the Corp, the Super Stallion will continue to provide the bulk of the MAGTF's heavy-lift requirement for some years to come.

‘On the Prowl’

The Sikorsky CH-53E Super Stallion is the largest helicopter in the United States Marine Corps; and with its awesome carrying capacity it is capable of transporting any aircraft within the USMC fleet other than the KC-130J Hercules. With its enormous 16 ton payload, it is more than capable of transporting pretty much anything, including troops and vehicles over a 50 mile range.

The ‘Snake Pit’On the western side of MCAS Yuma are two areas known as the Calas, both of which are able to conduct autonomous aircraft operations. The two Calas were in use during WTI 2-15, with the Bell AH-1W, AH-1Z and Bell UH-1Y helicopters from a variety of east and west coast based HMLA (Helicopter Marine Light Attack) squadrons operating from the North Cala; with the South Cala playing host to the various fixed-wing squadrons for the KC-130, FA-18 and AV-8 squadrons.

Held in the Spring and Autumn of each year, MAWTS-1’s biannual Weapons and Tactics Instructor Course is the Marine Corps only service- level exercise that provides students and supporting units the full spectrum of combat operations, from small unit inserts to non-combatant evacuation operations (NEOs), to infantry battalion heli-borne lifts into the heart of a sophisticated enemy’s battlespace. Exposing the prospective WTI's to the unique array of capabilities the MAGTF possesses is the hallmark of the training programme. Aside from a rigorous academic curriculum, students participate in numerous graduate level exercises that showcase every function of Marine aviation. These evolutions, such as anti-air warfare, assault support tactics, offensive air support and ground based air defence, culminate in a series of final exercises that integrate joint, conventional and special operations forces.

VMFT-401's aircraft were probably amongst the busiest during the WTI course

Flying numerous missions from early morning, through the afternoon and into most evenings

The electronic warfare element was of course provided by the venerable Grumman EA-6B ProwlerFour such aircraft from VMAQ-3 took up temporary residence at Yuma for the WTI, along with a US Air Force E-3 Sentry and an E-8

This VMM-261 machine illustrates perfectly how the rotor-blades fold to decrease the space required to store the aircraft when on a boatIt is worth noting that the wing section also rotates 90 degrees to decrease its cross-section even further

This VMFA-122 FA-18C carefully threads its way back to its parking spot after a mission over the Yuma ranges

The Lockheed-Martin F-35B Lightning II first took part in a WTI back in 2014, with its role being somewhat limited at the time to SCAR (strike co-ordination and reconnaissance), escort and area defense missions. During WTI 2-15 the aircraft began to take a more prominent role, with close air support, armed reconnaissance and anti-air warfare missions being flown. WTI 2-15 also saw the F-35 execute 4th/5th generation integration with the FA-18 Hornets taking part in WTI and plans are now in place for the first F-35B student class to take place during WTI 2-16, which is scheduled for the Spring of 2016.

Mid-morning on the ramp at Yuma, a little attention from the ground crews is in hand for this CH-53

An AH-1Z Viper in the foreground, with a UH-1Y Venom being prepared by its crew in the background

A typical WTI involves more than 200 instructors, some 90 aircraft and around 4,000 personnel. The course consists of part classroom instruction combined with a rigorous flight curriculum and is intended to build communication between pilots and troops on the ground, so when they are performing a variety of real-world missions, such as transporting troops, providing close-air support, evacuating non-combatants and performing humanitarian assistance and disaster recovery efforts, they will work together smoothly and efficiently. During their training, students are taught about a variety of weapons and how they are used, tactics and how best to utilise them together with other Marine aviation units, as well as command and control systems. When the flight stages of the course are taught, the students learn about the capabilities of their aircraft before going on to fly with similar types of aircraft and ending with all of the units participating in a week-long final exercise, during which they plan and perform a combined-arms operation within the city limits of Yuma and Brawley, California. So simply put, having completed the classroom element of the course, the pilots then have the pleasure of just going out, flying and 'blowing shit up'.

The Weapons & Tactics Instructor Course is an advanced instructor training course for all elements of the United States Marine Corps, enabling them to ‘train like we fight’ and to do so in venues and scenarios that extract maximum value for the dollar. Lt Gen Jon ‘Dog’ Davis (Deputy Commandant for Marine Aviation) said in the 2015 Marine Aviation Plan, “We will operate and cross-train with our MAGTF team-mates as the going-in proposition vice the exception. With alleged Russian separatists shooting down airliners with advanced SAM (surface to air missile) systems and Hezbollah striking Israeli ships with shore-based cruise missiles, we need to be ready. The bottom line is that we need to train and be ready for operations across the range of military operations—now".

Pilots, weapon system operators, ground combat and combat support service officers from throughout the Marine Corps come to MCAS Yuma to take part in the course, with the WTI's primary purpose being to train weapons and tactics instructors, who will then return to their squadrons and pass on what they have learned. The course is planned to develop them as tacticians, instructors and integrators of everything that Marine aviation is able to do for the MAGTF. Only the top 10% of Marines ever get to attend a WTI, which roughly equates to one Marine from every aviation unit. The WTI however is not just open to the US Marine Corps. Other branches of the US military, as well as friendly foreign nations send troops and pilots to attend the course.

#167112 was one of five Lockheed KC-130J Hercules temporarily based at Yuma for WTI

This one is from VMGR-252 at Cherry Point, NC

The 'Snipers' aircraft are painted in a variety of nice adversary schemes

Just another day at WTI; with this FA-18D basking in the typical 95ºF heat of a Spring day in Yuma

It's important to remember that there is a lot of live ordnance expended during every WTI. That's why before even being allowed access to the various ramps at Yuma we had to undergo an ordnance brief. This involves a presentation on the various types of ordnance we might encounter and how it is 'flagged up' as being in use around the various ramps on the airfield. During our time photographing the wide range of aircraft attending WTI, it was clearly apparent that aircraft and helicopters were flying the majority of missions with some kind of ordnance load, be it both live and inert. Flying an aircraft with a munitions load under simulated combat conditions is very different; the aircrafts flight characteristics are different, range and performance are affected and it is important that the students get to experience all of this throughout the WTI course.

This Osprey isn't going anywhere in the short-term, as its starboard rotor-blades are undergoing some maintenance work

Concentration is the key, as this FA-18 'fighter-jock' focuses on keeping his steed straight and level

The system includes both infrared and visible light sensors, two digital tape recorders, a Reconnaissance Management System (RMS) and an interface with the Phase II APG-73 Radar, which records synthetic aperture radar imagery

The ATARS fits in the nose in place of the normal M61 20mm cannon, with a datalink pod mounted on the centerline station

The digital data link transmits imagery and auxiliary data to any Common Imaging Ground/Surface Station (CIG/SS), including the Joint Services Imagery Processing System (JSIPS) or a shore-based Marine Tactical Exploitation Group (TEG)

The twin-tail configuration of the F-35B is evident in the photograph aboveAll the missions we saw at Yuma resulted in the aircraft making normal landings and not utilising the aircraft's STO/VL capability